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No exploitation reportedFix available

CVE-2021-40364

No exploitation reported by the sources we read.

  • Published2021-11-09
  • WeaknessCWE-532

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A vulnerability has been identified in SIMATIC PCS 7 V8.2 (All versions), SIMATIC PCS 7 V9.0 (All versions < V9.0 SP3 UC04), SIMATIC PCS 7 V9.1 (All versions < V9.1 SP1), SIMATIC WinCC V15 and earlier (All versions < V15 SP1 Update 7), SIMATIC WinCC V16 (All versions < V16 Update 5), SIMATIC WinCC V17 (All versions < V17 Update 2), SIMATIC WinCC V7.4 (All versions < V7.4 SP1 Update 19), SIMATIC WinCC V7.5 (All versions < V7.5 SP2 Update 5). The affected systems store sensitive information in log files. An attacker with access to the log files could publicly expose the information or reuse it to develop further attacks on the system.

Timeline

dates in UTC
  1. 2021-11-0912:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-40364?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-40364?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Siemens simatic wincc
BranchAffectedFixed in
7.4≤ 7.4no fix published
7.5= 7.5no fix published
15.x= 15no fix published
16.x= 16no fix published
17.x= 17no fix published
Siemens simatic pcs 7
BranchAffectedFixed in
9.x≥ 9.0, < 9.19.1
8.2≤ 8.2no fix published
9.1= 9.1no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Vendor advisories

  • ICSA-21-315-03 CISA8 known affected

    Siemens SIMATIC WinCC (Update E)

    SIMATIC PCS 7 V8.2 · SIMATIC PCS 7 V9.0 · SIMATIC PCS 7 V9.1 · +5 more

Full record on NVD

Fix

  1. Vendor fix CISA ICSA-21-315-03 · 1 productUpdate to V8.2 SP1; then update SIMATIC WinCC to V7.4 SP1 Update 19 or later version to fix CVE-2021-40358 and CVE-2021-40364
  2. Vendor fix CISA ICSA-21-315-03 · 1 productUpdate to V15 SP1 Update 7 or later version
  3. Vendor fix CISA ICSA-21-315-03 · 1 productUpdate to V16 Update 5 or later version
  4. Vendor fix CISA ICSA-21-315-03 · 1 productUpdate to V17 Update 2 or later version
  5. Vendor fix CISA ICSA-21-315-03 · 1 productUpdate to V7.4 SP1 Update 19 or later version
  6. Vendor fix CISA ICSA-21-315-03 · 1 productUpdate to V7.5 SP2 Update 5 or later version

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub

Sources

  • CNACVSS 3.15.5read 2026-10-23
  • NVDCVSS 3.15.5read 2026-10-23
  • NVDCVSS 2.02.1read 2026-10-23
  • CNAweakness (CWE)CWE-532read 2026-10-23
  • NVDweakness (CWE)CWE-532read 2026-10-23
  • FIRST EPSSEPSS score0.2 %2026-10-23

Technical details

CVSS v3 Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Published
2021-11-09
Last Modified
2026-06-17
NVD status
Modified

Frequently asked questions

What is CVE-2021-40364?

A vulnerability has been identified in SIMATIC PCS 7 V8.2 (All versions), SIMATIC PCS 7 V9.0 (All versions < V9.0 SP3 UC04), SIMATIC PCS 7 V9.1 (All versions < V9.1 SP1), SIMATIC WinCC V15 and earlier (All versions < V15 SP1 Update 7), SIMATIC WinCC V16 (All versions < V16 Update 5), SIMATIC WinCC V17 (All versions < V17 Update 2), SIMATIC WinCC V7.4 (All versions < V7.4 SP1 Update 19), SIMATIC WinCC V7.5 (All versions < V7.5 SP2 Update 5). The affected systems store sensitive information in log files. An attacker with access to the log files could publicly expose the information or reuse it to develop further attacks on the system.

Is CVE-2021-40364 actively exploited?

Active exploitation of CVE-2021-40364 has not been confirmed. Its EPSS score was 0.2% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-40364?

CVE-2021-40364 has a CVSS v3 base score of 5.5 (MEDIUM severity), with vector string CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

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